Useful decorator around the django.contrib.sites package for view functions.

decorator.py

from django.conf import settings
from functools import wraps
from django.contrib.sites.models import get_current_site
from django.http import HttpResponseNotFound


def main_site_only(function):
    "Use this decorator on views that should only be visible on your main site"
    @wraps(function)
    def decorator(request, *args, **kwargs):
        if get_current_site(request).id in settings.SITE_ID:
            return function(request, *args, **kwargs)
        else:
            # Change this to a TemplateResponse if you want to return a template
            return HttpResponseNotFound()
    return decorator